DOC: local py.typed for users

[twoertwein]

xref #44223 (comment)

[twoertwein]

Starting with 1.4, it might be useful to slowly start advertising pandas's built-in type annotations (before pandas becomes a py.typed library). Specifically, I can imagine informing the maintainers of https://github.com/microsoft/pylance-release They have often pandas type issues as pylance ships the Microsoft type stubs.

Could maybe even have a note in the whatsnew?

[jreback]

happy to have a section in the whats new and the docs as well

[jreback]

can you merge master

[twoertwein]

@jreback green'ish, doc seems to fail on master as well

[twoertwein]

I don't think it makes sense to advertise experimenting with a local py.typed at the moment. People who will test it will be swamped in error messages. I tested it with my own code: many functions return a Union instead of using overloads (read_csv, basically all functions taking inplace, and indexing with list-like vs. scalars).

I think the earliest it makes sense to advertise experiments with py.typed is with 2.0 (when we can make most arguments keyword-only arguments: makes most overloads possible).

[jreback]

thanks @twoertwein this is good.